ENTP: The Mad Scientist
The ENTP, like the ENTJ, is charismatic, outgoing, and intelligent. ENTPs are often quickwitted, clever, and genial; they typically display a highly organized, rational cognitive ability which makes them natural scientists and inventors.
ENTPs are creative, complex people who seek to improve their understanding of the natural world, usually by building armored fifty-story-tall robotic monsters with iron jaws and death-ray eyes, or by creating genetically mutated plagues that spread unstoppably across the land, turning all who are contaminated into mindless zombie drones. They are less likely to want to conquer the world than to destroy it utterly, reducing it to nothing but slag and rubble--though this is often merely a side-effect of their pursuit of knowledge.
RECREATION: ENTPs enjoy recreational activities which challenge them physically and intellectually, such as water skiing and porting Linux to their iPods. They are also fond of collecting gadgets like combination cellpone/PDAs and orbiting arsenals of brain lasers, which they may port Linux to as well.
COMPATIBILITY: ENTPs and ENTJs make natural companions, as the one's unspeakable hunger for power complements the other's unspeakable hunger for knowledge. They do not generally build successful relationships with ESFJs, as ENTPs they are prone to behaving in inconveniently erratic ways, which pisses ESFJs off to no end; and because ENTPs simply do not know how to dress appropriately for formal occasions.
Famous ENTPs include Spencer Silver (the inventor of Post-It Notes), Robert Oppenheimer, and Dr. Jeckyll.